It's a software bug that needs to be fixed via a software update. There is no solution besides Samsung fixing the issue. They are slacking off. I have been using samsung phones since the Samsung Captivate. If they don't fix this issue my next phone will be a Google Pixel. They get the newest updates and they fix issues. This is unaccceptable Samsung.
I received an update yesterday (3-23-20) for my Xfinity Mobile S9+ that appears to only be a security patch. Still no fix for this issue. I have been waiting patiently for a fix since Android 10 was pushed to my phone and have been quite disappointed.
I do apologize that you are running into this issue and you tried a few troubleshooting steps. I am also sorry to hear that you had to do a factory rest on your device. Did you manage to back up your information before the factory rest? If you don't mind there are a few solutions you might want to try.
If you managed to back up your information and like you mentioned you did a factory rest. Make sure when you restore your information that all your apps are updated.
If the above solution did not work out for you. Turn on notification sound.
If the two solutions did not work. When you have time please head to a local authorized Samsung Care or Samsung Authorized location and ask for a phone diagnostics to check if there is anything else that will trigger your notifications from not appearing for you. The other suggestion I would advise is to ask them to do a software reinstallation for you on their machines. Most of the time this fixes any issues.
Fill free to go here to check if there are any locations that are near you (https://www.samsung.com/us/support/service/locations/). Thank you for being a part of the Samsung family.
If this is helpfull please fill free to leave alike and a share.
@dave1977nj would you be so kind if you do have time in your day try one of our repair locations or authorized location just to truly see what is going on with your device. I understand your frustration. I really want to get to the bottom of why your led notification are not functioning as they are intended to.
@Constantino_A Please look at many of the comments in this thread. From what I gather this may only effect UNLOCKED Phones that have an LED.
In general for those of us with an UNLOCKED PHONE having a LED what we all did was UPDATE to ANDROID 10. This update 'broke' notifications with the LED. It is NOT hardware. It is FIRMWARE. The latest code was REALLY for the Latest Phones. The Latest Phones do NOT have a LED.
The Android 10 release has to be updated with a decision: HAS LED? if the Device has an LED the LED code is run. If it does not have an LED the EDGE LIGHT code is run.
I will say this again. When the code is Updated it will run phones with LEDs and PHONES without LEDs. Now it only runs phones without LEDs.